Already nearing blockbuster status, Immunex Corp.’s Enbrel received FDA approval to treat psoriatic arthritis, thus becoming the first product to be cleared for that indication and further fueling the drug’s growth.
“It’s really a major advantage for a lot of patients with psoriatic arthritis,” said Laura Hammill, vice president of Enbrel marketing at Immunex. “It’s similar to what happened when it was approved for rheumatoid arthritis these patients didn’t have any options.”
Enbrel (etanercept) received marketing approval to reduce the signs and symptoms of active arthritis in patients with psoriatic arthritis. The product can be used alone, or in combination with methotrexate, in patients who do not respond adequately to methotrexate alone. The approval means a healthy increase in Enbrel’s market potential, even healthier than previously thought by some.
Estimations had the psoriatic arthritis population set at about 300,000 diagnosed patients in the United States, but the National Psoriasis Foundation said a recent study it conducted showed that about 1 million adults have the disease.
“We are excited because it is the first of this new type of drug that is available for people with psoriatic arthritis and psoriasis,” said Molly Marshall, marketing and public relations manager at the National Psoriasis Foundation, based in Portland, Ore.
In the past, Hammill said, patients have been misdiagnosed and underdiagnosed. They often may bounce between dermatologists and primary care physicians, trying to treat the skin conditions of the disease, without understanding what it is they truly have: psoriatic arthritis. Having an approved product for the indication should assist in alleviating that, she said.
“This will help us to put psoriatic arthritis on the radar screen,” she told BioWorld Today. “I feel it’s not on the top of the mind for a lot of dermatologists. This may help people understand what they have. It all goes back to the blurriness between psoriasis and psoriatic arthritis.”
Enbrel is designed to bind to tumor necrosis factor and render it biologically inactive, thus resulting in a reduction in inflammatory activity. Psoriatic arthritis patients in the past have used methotrexate, cyclosporin and even aspirin to fight their symptoms, Marshall said, adding that Remicade (Centocor Inc., of Malvern, Pa.) has been used to some success. That product is still in development and not approved by the FDA for psoriatic arthritis.
Immunex, of Seattle, is in the process of combining with Amgen Inc., of Thousand Oaks, Calif., in a merger valued at $16 billion a whopping price based on both Enbrel’s success so far and its potential upside. Since the merger was announced, it’s “been business as usual,” Hammill said, which means Enbrel. Immunex’s year-end results have not been released, but the drug brought Immunex $545.6 million in 2001’s first nine months. Immunex struggled to produce enough Enbrel to meet the demand in 2001, but it has addressed that issue by adding manufacturing capability.
Hammill said Immunex would need to “do our due diligence” to determine how the larger estimates for the psoriatic arthritis population would affect total Enbrel sales. Estimates for this year’s sales have not been made, she said.
First launched in November 1998, Enbrel is indicated for reducing signs and symptoms and inhibiting the progression of structural damage in patients with moderately to severely active rheumatoid arthritis. It can be used in combination with methotrexate in patients who do not respond adequately to methotrexate alone. Also, it is approved for reducing signs and symptoms of moderately to severely active polyarticular-course juvenile rheumatoid arthritis in patients who have had an inadequate response to one or more disease-modifying anti-rheumatic drugs. Its third approval is for reducing signs and symptoms of active arthritis in patients with psoriatic arthritis. It can be used in combination with methotrexate in patients who do not respond adequately to methotrexate alone.
Wednesday’s approval makes four indications, but Immunex sees more on the horizon in the near term. Immunex is investigating ankylosing spondylitis and also psoriasis. Not to mention that the psoriatic arthritis market is now estimated to be more than three times what it was previously thought.
“This is the fourth approved indication and there are two more on the radar screen,” Hammill said. “Enbrel in itself is a franchise and it continues to drive the growth of the organization. Enbrel continues to stand up and meet the challenges we think it can.”
Immunex’s stock (NASDAQ:IMNX) fell 8 cents Wednesday to close at $27.58.